1. Field of the Invention
The present invention relates to a vibration isolating apparatus used for supporting an engine mainly for a compact vessel or an automotive vehicle in such a manner as to isolate a vibration.
2. Description of the Related Art
Conventionally, as a vibration isolating apparatus provided for supporting an engine corresponding to a vibration generating source, for example, in a compact vessel in such a manner as not to transmit a vibration thereof to a vessel body, a vibration isolating apparatus comprising an upper mounting metal fitting to which a bolt for mounting an engine is provided in a projecting manner, a lower mounting metal fitting mounted to a body end and a body rubber portion disposed between both of the metal fittings is used.
Further, in order to increase an effect for reducing a vibration and a sound of the engine, it is considered to use a liquid-enclosing type vibration insulating apparatus which is structured such that an opening portion close to a lower end in a cylindrical body metal fitting and a lower end mounting metal fitting disposed below the same are connected to each other by a body rubber portion disposed between the two metal fitting, and an upper end mounting metal fitting is fixedly attached to an upper end portion of the body metal fitting so as to form two liquid chambers communicating between a diaphragm made of a rubber film and disposed therewithin and the body rubber portion by an orifice.
As the vibration isolating apparatus of the above type, particularly in order to support an engine having a heavy weight for a compact vessel without a slackness and a play and optionally adjust a supporting height, the applicant of this invention has suggested that a support portion provided in the upper end mounting metal fitting in a projecting manner and constituted by an engine mounting bolt is structured such as to be a double nut construction constituted by a washer based nut and a nut for preventing a slackness and removal (JP-A-08210429(1996) (Japanese Patent Unexamined Publication No. 8-210429)).
In the suggested apparatus mentioned above, as means for restricting a large displacement due to the engine vibration, a part of the vibration isolating base body has a projecting portion to which a projecting piece from the body metal fitting is inserted and a stabilizer is fixed to the upper end mounting metal fitting, so that the stabilizer is elastically brought into contact with the projecting portion at a time of a large displacement to a vertical direction or a direction perpendicular to the axial direction, thereby achieving a stopper effect.
In this case, since the stopper portion is brought into contact with only one side of the vibration isolating apparatus and the stabilizer is fixed to only one fastening portion of the engine mounting bolt, a support strength serving as a stopper is not sufficient, so that there is a problem in a durability, for example, a deformation of the stabilizer is generated at a time when a large load (a large displacement) is given.
Particularly, as a vibration isolating mount for supporting the engine for a compact vessel, in view of the point mentioned above, it is desired that the vibration isolating apparatus is further improved.